ovs-appctl, for querying and controlling Open vSwitch daemon
usage: ovs-appctl [TARGET] COMMAND [ARG...]
Targets:
  -t, --target=TARGET  pidfile or socket to contact
Common commands:
  list-commands      List commands supported by the target
  version            Print version of the target
  vlog/list          List current logging levels
  vlog/list-pattern  List logging patterns for each destination.
  vlog/set [SPEC]
      Set log levels as detailed in SPEC, which may include:
      A valid module name (all modules, by default)
      'syslog', 'console', 'file' (all destinations, by default))
      'off', 'emer', 'err', 'warn', 'info', or 'dbg' ('dbg', bydefault)
  vlog/reopen        Make the program reopen its log file
Other options:
  --timeout=SECS     wait at most SECS seconds for a response
  -f, --format=FMT   Output format. One of: 'json', or 'text'
                     (default: text)
  --pretty           Format the output in a more readable fashion.
                     Requires: --format=json.
  -h, --help         Print this helpful information
  -V, --version      Display ovs-appctl version information